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Furnace not lighting/Gas line freezing?

Came home from work last night to find that the heat had stopped working on the coldest day of the season. (20's all day, 1/4" of freezing rain/sleet fell)

Unit is an outdoor Trane furnace/AC "all in one", natural gas. It was installed in 2006, and had never been serviced.

Luckily, the one HVAC guy that answered his phone happened to be a few miles away, he came out at around 8PM, despite the bad road conditions.

The gas valve seemed to be bad, so he swapped in a new one. No improvement, gas wasn't getting to the valve. He then got a torch and warmed up the regulator, which happens to next to the unit, exposed to the weather, and the black plastic cap had popped off (months ago) and was sitting nearby. That got gas flowing to the valve, but it still didn't light. Turns out he put the valve in backwards, so he reinstalled. (obviously he'd had a long day)

Now the gas would light, but wouldn't stay lit. He checked the flame sensor, and it had white residue on it, so he cleaned it off...still nothing. This particular unit has two...burners (?), one has the flame sensor and the other has the ignitor. he said the channel between the two was dirty, so the flame from the lit burner wouldn't get over to light the other.

After all this, everything seemed to work. House was warm until I went to bed, but I woke up to a cold house.

It's still cold outside, roads are still icy, etc.

The only thing I felt comfortable doing myself was to cycle the power...no ignition. I took a hair dryer to the regulator, and tried again. Furnace has been on for about an hour now, hasn't turned off since the house is still cold.

I'm left wondering what the original problem was...the valve, or the regulator, or a combination of several things? The problem doesn't seem to be fixed, should I go back to the original repair guy, or find someone else? What should I request that he do? Do regulators "go bad"? Should I do something to keep it warm, maybe heat tape or...? Could there be moisture trapped within the regulator?

Came home from work last night to find that the heat had stopped working on the coldest day of the season. (20's all day, 1/4" of freezing rain/sleet fell)

Unit is an outdoor Trane furnace/AC "all in one", natural gas. It was installed in 2006, and had never been serviced.

Luckily, the one HVAC guy that answered his phone happened to be a few miles away, he came out at around 8PM, despite the bad road conditions.

The gas valve seemed to be bad, so he swapped in a new one. No improvement, gas wasn't getting to the valve. He then got a torch and warmed up the regulator, which happens to next to the unit, exposed to the weather, and the black plastic cap had popped off (months ago) and was sitting nearby. That got gas flowing to the valve, but it still didn't light. Turns out he put the valve in backwards, so he reinstalled. (obviously he'd had a long day)

Now the gas would light, but wouldn't stay lit. He checked the flame sensor, and it had white residue on it, so he cleaned it off...still nothing. This particular unit has two...burners (?), one has the flame sensor and the other has the ignitor. he said the channel between the two was dirty, so the flame from the lit burner wouldn't get over to light the other.

After all this, everything seemed to work. House was warm until I went to bed, but I woke up to a cold house.

It's still cold outside, roads are still icy, etc.

The only thing I felt comfortable doing myself was to cycle the power...no ignition. I took a hair dryer to the regulator, and tried again. Furnace has been on for about an hour now, hasn't turned off since the house is still cold.

I'm left wondering what the original problem was...the valve, or the regulator, or a combination of several things? The problem doesn't seem to be fixed, should I go back to the original repair guy, or find someone else? What should I request that he do? Do regulators "go bad"? Should I do something to keep it warm, maybe heat tape or...? Could there be moisture trapped within the regulator?

Thanks!

Use a torch on a GAS regulator??? Even a long day does not account for putting a gas valve in backwards. There are a number of possibilities. You need to make another phone call.

The regulator is just upstream from the unit. I texted (!) the guy and he put in a new regulator...hopefully that takes care of it. He didn't charge anything, so that's a plus...though his helper was smoking during the process, which seemed odd.

I'm reluctant to pay for the regulator to be relocated considering it hasn't been an issue for 7 years... Would some sort of cover (other than the plastic cap) to keep the ice/snow away suffice?

They make a cover for them to keep the elements out but still let them breath. The vent cap being broke off is what caused the problem {the plastic piece}it let water in to the regulator. "NEVER USE A TORCH ON A REGULATOR"

The regulator is just upstream from the unit. I texted (!) the guy and he put in a new regulator...hopefully that takes care of it. He didn't charge anything, so that's a plus...though his helper was smoking during the process, which seemed odd.

I'm reluctant to pay for the regulator to be relocated considering it hasn't been an issue for 7 years... Would some sort of cover (other than the plastic cap) to keep the ice/snow away suffice?

Never allow service people to smoke in your home. If they must smoke, tell them to sit in their vehicle.

A torch on a gas regulator is a guy looking to make headlines.

If an outdoor regulator froze up, contact the utility about replacement and sizing. Inspect and measure all your gas lines to ensure proper sizing. If you have a Medium Pressure regulator indoors near the equipment, have another pro ensure it is installed to code with a shutoff immediately upstream, a sediment trap to protect it and a means of measuring outlet pressure. As noted, if in a confined space, the vent must be routed to the outdoors.

If the protective cap is off the outdoor regulator it must be replaced ASAP. If ice gets in there, it can damage the reg. Call the utility.

Never allow service people to smoke in your home. If they must smoke, tell them to sit in their vehicle.

A torch on a gas regulator is a guy looking to make headlines.

If an outdoor regulator froze up, contact the utility about replacement and sizing. Inspect and measure all your gas lines to ensure proper sizing. If you have a Medium Pressure regulator indoors near the equipment, have another pro ensure it is installed to code with a shutoff immediately upstream, a sediment trap to protect it and a means of measuring outlet pressure. As noted, if in a confined space, the vent must be routed to the outdoors.

If the protective cap is off the outdoor regulator it must be replaced ASAP. If ice gets in there, it can damage the reg. Call the utility.

He was outside, as was the unit and regulator. Again, the regulator is just upstream from the unit, down from a cutoff and and a trap, not the gas companies problem. The cutoff was off when he was heating it with the torch, still seemed a bit odd though.

Someone should come up with a better designed regulator that doesn't depends on a flimsy plastic cap to keep it functional...